Photocopy machine having a variable speed copy paper cutter



PHOTOCOPY MACHINE HAVING A VARIABLE SPEED COPY PAPER CUTTER Filed Oct. 26, 1966 CLUTCH I---4--| CUTOFF U S. S |------4 S4 o i 2 2a '3 4 4a 5 JNVENTORS Gordon W; Nichols BY Edward J. Rodin WWW ATTORNEY United States Patent "ice 3,398,619 PHOTOCOPY MACHINE HAVING A VARIABLE SPEED COPY PAPER CUTTER Gordon W. Nichols, Binghamton, and Edward J. Radin, Johnson City, N.Y., assignors to GAF Corporation, a corporation of Delaware Filed Oct. 26, 1966, Ser. No. 589,693

' 7 Claims. (Cl. 83363) The present invention relates to photocopy machines and more particularly to machines in which the copy paper is not pre-cut but delivered from a roll, to be cut to size determined by the size of the original to be copied.

The copy paper should be cut accurately to the same size as the original. It must not be smaller, lest information to be copied is cut off; and it should not be larger, both to avoid waste and for neatness of the copy received. When the speed of operation, that is, the speed of the feed of the copy paper, is substantially constant, then cut-off knives and operating units therefor can be readily designed. When, however, there is wide variation in the speed of feed of the paper, the operating requirements placed on the knife become severe. This problem particularly arises in machines in which light shines through an original which is passed over a predetermined exposure area in the machine, and the machine is designed to copy both from ordinary heavy grade paper, such as 20-pound bond paper, as well as from tracing cloth and onion skin. In such apparatus, the variation in speed of feeding, and thus the passage past the exposure area, may vary from 2 to 60 feet per minute, resulting in a speed range of 1:30.

It is an object of the present invention to provide a copy machine having cut-01f apparatus which accurately cuts paper in spite of wide variation of paper feed speed.

Briefly, in accordance with the present invention, the photocopy machine has a feed means for copy paper to feed the copy paper along a predetermined path. A knife, or cut-off assembly, is arranged in the path of the copy paper. The knife is operated by an electric solenoid or other electromagnetic device, The copy paper itself is fed by an electric mot-or. The speed of the motor can be set manually over a wide range, or can be determined automatically. The point of time at which the operating means, that is, the solenoid or other electromagnetic device, operates the knife, in relation to the position of the copy paper within the machine, is determined not only by the position of the copy paper, but further, by the speed of its feed. This speed can be sensed, for example, by obtaining a representative value of voltage from the armature of the motor itself. Thus, when the speed of feed is very high, the cut-off mechanism or knife is caused to operate somewhat sooner than when the speed is low, so that the amount of paper passing the knife before the actual cutting occurs is approximately constant in any case, and independent of the speed of the paper transport.

Actual operation of the knife solenoid or motor can be initiated by sensing switches, positioned to cause switching action when the trailing edge of the original of the paper passes thereover. By staggering these switches along the feed of the original of the paper, earlier or delayed switching action can be obtained. The speed signal obtained from the motor is then used to control which one of the staggered switches controls the cut-off knife. For simplicity, a pair of such staggered switches can be used, and when the motor armature voltage exceeds a certain value, a relay switches over from the normally engaged feeding, or slow-speed switch, to the alternatively engaged trailing, or high-speed switch.

The structure, organization and operation of the invention will now be described more specifically in the fol- 3,398,619 Patented Aug. 27, 1968 lowing detailed description with reference to the accompanying drawings, in which:

FIG, l is a schematic view illustrating the feed arrangement for both the original and the copy paper, and the placement of the switches, wherein conventional parts are illustrated in block, or schematic form;

FIG. 2 is a circuit diagram of the switching arrangement in the copy machine of the present invention, and

FIG. 3 is a timing diagram illustrating the timing relationship of the various switches and elements of the apparatus.

Referring now to the drawings, and particularly to FIG. 1: copy paper 10 is reeled from a supply reel 11, passed over an idler roller 12, then between a pair of feed rollers 13, 13', which may be spring loaded to be pressed against each other as shown schematically, to a cut-off mechanism generally illustrated at 14. The cut-off mechanism consists of a gate 15 and a movable knife 16, rotatably mounted to shear paper off extending through gate 15. The cut-off mechanism 14 is operated by a solenoid, or other electromagnetic operating means 17 (FIG. 2) and not further illustrated in FIG. 1, since such cut-off mechanisms are well known. The paper, after passing the cut-off mechanism, is passed over a guide 18 to a feed belt 19 for delivery to an exposure area. The belt 19 runs over an idler roller 22, and a drive roller 23 as well as beneath an idler roller 20.

Drive roller 13 is driven from a variable speed motor 25, as indicated by the dashed connection, with an electromagnetic feed roller clutch 26, well known in itself, being interposed in the drive connection. The variable speed motor 25 further drives roller 23, as indicated by the dashed lines, to translate belt 19, in a manner well known in the art.

The original to be copied is fed over a platform guide or apron 30, which is suitably perforated to contain contacts of sensing switches which sense the leading and trailing edge of the original on guide 30. Suitable hold down means to assist in the sensing may be provided and are not shown for simplicity. Arranged beneath the guide 30 are three switches; a leading edge sensing switch S2, a leading cut-01f switch S4, and a trailing cut-off switch S5. As will appear below, switch S4 is placed in circuit for slow speed operation, and switch S5 is placed in circuit for high speed operation.

The motor, the cut-off knife, the feed roller clutch, and the switches are interconnected as shown in FIG. 2. Power is supplied to the apparatus over incoming line 40, which may be 110 volts AC, A master ON-OFF switch S1 is in series with the line to provide main control and power the motor 25. Likewise in series with the line is a conventional fuse F, In series with switch S1 is the leading edge sensing switch S2, which when closed connects a full wave rectifier supplying power of approximately volts DC to either the clutch 26 or the solenoid of operating mechanism 17 for the knife assembly 14, as will be hereinafter more fully described. Double throw single pole switches S4, S5 are connected in parallel, with their common connections brought to alternately engaged relay contacts S3; the common connection from relay contacts S3 are returned to the other pole of the DC sup ply. The floor line position of the contacts as shown is the normal or rest position with switch S1 being open, or off.

The contacts S3 are controlled by relay coil 41, which in series with a limiting resistor 44 is connected across the armature and senses the armature voltage, as well known in the art. If the armature voltage exceeds a certain value, relay coil 41 will be sufficiently energized to pull the contact S3 from the solid line position over to the other contact. The speed of the motor itself can be controlled either manually bysettingofa manual rheostat'42 or by an automatic speed control 43 which automatically determines the time exposure required to make a copy.

. The-operation of the apparatus can best be explained in connection with FIG. 3. First, main ON-OFF switch S1 (FIG. 2) is closed to provide power to motor 25. At this time copy paper is not being furnished from roll 11, since S2 is open, and thus the feed roller 13 is not coupled to motor 25. Therefore the original is placed on guide 30 and slide forward to first engage switches 85, S4, causing them to change over from the solid line position to the not-drawn position (FIG. 2) so that DC circuit will be established through clutch 26, regardless of the position of switch 33 if the rectifier is energized. Point zero in FIG. 3 is the rest position; point 1 shows the position when switch S1 is turned on energizing the motor 25. Point 2 illustraes the closing of switch S and shortly thereafter point 2a the closing of switch S4. As the original is manually advanced further, it will hit the leading edge switch S2 (point 3, FIG. 3) and S2 will close. Power will be applied to the clutch since switches S4, S5, are in their non-drawn position. Both copy paper as well as the original will feed toward roller 20 and over the belt, where they will be fed together in overlying position for exposure and making of the copy.

If the speed of feeding is slow, that is, if the armature voltage from motor 25 is insuflicient to cause changeover of relay contact S3 from the solid line position, the copy paper will continue feeding until the trailing edge of the original hits switch S4; prior to that time it releases switch S5 which, however, is ineffective in view of the solid line position of relay contacts S3. As soon as contact S4 changes from the not-drawn position to the solid line position in FIG. 2, the clutch 26 will be deenergized, feed of additional copy paper will stop and the cut-01f operating solenoid 17 will be energized, causing rotation of knife 16' and cut-ofi. This is the position at 4a, FIG. 3, and the dotted line position of the cut-oil therein. The motor will continue to turn, feeding the remainder of the copy paper and the original between roller 20 and belt 19 for exposure, and to another transport means (not shown) for completion of the copy process. After the trailing edge of the original releases switch S2 (point 5, FIG. 3), the copy paper feed and cut-olf mechanism will revert to rest, regardless of the opening or closing of switch S1.

If the armature voltage of motor 25 is suflicient to cause change-over of relay contacts S3, the same sequence will take place except that the clutch will stop and the cut-off will occur already somewhat earlier, that is, when the trailing edge of the original engages contacts S5 (see point 4 and solid line position of cut-off in FIG. 3). Thus, when the speed of the paper is high, the cut-off mechanism will operate a little sooner, causing less paper to be fed through gate in the time it takes the knife to cut than if contact S4 were to operate the knife. Thus, for higher speed feed the amount of cop-y paper fed is the same as the amount fed for low speed feed.

As will be obvious, a plurality of switches can be used, staggered along the path of travel of the original, that is, along guide 30, and switch S3 can then be provided with a greater number of contacts than two with a suitable operating mechanism therefor, causing selective engagement of these contacts in accordance with voltage derived from the armature of motor 25, to sense the speed and thus place the proper switch in the path of the original inserted with the cut-off mechanism.

The speed of motor 25 can be sensed by means other than the armature reaction voltages; for example, a tachometer can be used, or the speed of feed of the paper itself can be determined. Switches, S2, S4, S5 are illustrated as mechanical contact switches, but they may be photo-electrically'or capacitatively operated, or may be switches taking other forms.

It should be understood that the foregoing disclosure relates to only a preferred embodiment of the invention, and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purposes of the disclosure, which do not constitute departure from the spirit and scope of the invention.

The invention claimed is:

1. A photocopy machine for making copies from an original onto a light-sensitive copy paper which is being fed from a copy paper roll, a variable speed feed means for feeding said copy paper in a predetermined paper feed path, said feed means including a variable speed electric mot-or; cut-oil. means for said copy paper; electrical means controlling the operation of said cut-off means; and means sensing the speed of said motor, said speed sensing means controlling the application of potential to said electrical means thus controlling the operation of said cut-off means, whereby the actuation of said cut-off means will be dependent on speed of feed of said copy paper.

2. A photocopy machine as recited in claim 1 including feed means for an original to feed original in a predetermined original feed path; a plurality of switch means located in the feed path of said original staggered in the direction of travel of said original along said feel path, and sequentially operable during the passage of the lead ing edge and trailing edge of said original traveling in said path; control circuit connections from said switches to said electrical means for controlling the operation of said cut-off means; and circuit control means energized in dependence on sensed motor speed to selectively close said controlled circuit connections.

3. A- copying machine as recited in claim 2 wherein a pair of switches are provided; a switch-over relay, having alternately engaged contacts and a coil, said contacts forming said controlled circuit connections and said coil forming said circuit control means.

4. A copying machine as recited in claim 3 wherein said relay coil is voltage sensitive, a representation of armature voltage of said motor controlling the operation of said relay coil to switch said contacts of said relay and selectively establish a circuit including either of said pair of switches and said electrical means controlling the operation of said cut-off means.

5. A copying machine as recited in claim 1 including feed means for an original to feed said original in a predetermined original feed path; a pair of switches placed in said original feed path, said switches being located staggered in the direction of travel of said original along said path so that one is forward of the other with respect to such direction of travel; said switches being connected in the circuit of said electrical means controlling the operation of said cut-off means; and a switch-over relay, said switch-over relay having its coil in circuit with said speed sensing means and its contacts interconnecting either one of said pair of switches with the means controlling the operation of said cut-off means, the forward one of said pair of switches being connected to said electrical means to control the operation of said cut-off means when said motor is turning slowly, the trailing one being connected to said electric means to control the operation of said cut-off means during high speed operation of said motor.

6. A copying machine as recited in claim 5 wherein said speed sensing means includes a connection to the armature of said motor; said switch-over relay coil being energized to cause operation of said relay and connection of said trailing switch, of said pair, whenever the armature voltage exceeds a predetermined level indicating high-speed operation of said motor.

7. A photocopy machine for making copies from an original onto a light sensitive copy paper which is being fed from a copy paper roll comprising a source of electrical power,

a variable speed driving means connected to said source of power,

a feed means coupled to said driving means for feeding said copy paper and said original in a predetermined path,

a coupling means electrically energizable for connecting said copy paper. roll to said variable speed driv ing means,

a platform guide for directing said original to said feed means,

an electrically activated cutting means located in a path between said feed means and said copy paper roll,

a plurality of switch means located on said platform guide and staggered in the direction of travel of said original along said guide and sequentially operable by the passage of the leading edge and trailing edge of said original,

and a speed sensing means for sensing the speed of said drive means and operable at a particular speed to couple a selected switch means to said power source whereby when the leading edge of said original passes over and thereby operates said selected switch means, said coupling means is energized to feed said copy paper from said tool toward said feed means until the trailing edge of said original passes over and thereby operates said selected switch means to de-energize said coupling means and actuate said cutting means.

References Cited UNITED STATES PATENTS FOREIGN PATENTS 1,184,214 12/1964 Germany.

696,432 9/1953 Great Britain.

WILLIAM S. LAWSON, Primary Examiner. 

1. A PHOTOCOPY MACHINE FOR MAKING COPIES FROM AN ORIGINAL ONTO A LIGHT-SENSITIVE COPY PAPER WHICH IS BEING FED FROM A COPY PAPER ROLL, A VARIABLE SPEED FEED MEANS FOR FEEDING SAID COPY PAPER IN A PREDETERMINED PAPER FEED PATH, SAID FEED MEANS INCLUDING A VARIABLE SPEED ELECTRIC MOTOR; CUT-OFF MEANS FOR SAID COPY PAPER; ELECMEANS; AND MEANS SENSING THE SPEED OF SAID MOTOR, SAID SPEED SENSING MEANS CONTROLLING THE APPLICATION OF PROTENTIAL TO SAID ELECTRICAL MEANS THUS CONTROLLING THE OPERATION OF SAID CUT-OFF MEANS, WHEREBY THE ACTUATION OF SAID CUT-OFF MEANS WILL BE DEPENDENT ON SPEED OF FEED OF SAID COPY PAPER. 